I don't have that much graphic design experience, but a couple of things stand out to me:- The bottom two images don't look like they belong there. The title, ensemble shot, and credit look together like the front cover of a book, but then there's random stuff on the bottom.- The font doesn't scream "Awesome" to me. Is that Arial?

Anyway, I had some free time and felt like being silly, so I came up with this. I thought the ensemble shot wasn't action-y enough to really convey Awesome, so I used the drawing of the guy jumping out the window.

I'm afraid I don't have the time to actual work out a rough like Selene, but I will give you a few opinions about making the cover a bit more dynamic.

1) I agree with Selene on the font; not very adventurous. Something bolder and more imposing may better fit the bill here. It should be as much of a character on your cover as the adventurers pictured there.2) The pyramid style alignment for you action scenes kind of drains the energy out of the cover. I would suggest moving the window guy to the top left, and then lead the eye straight down across the other images diagonally. Does that make sense without a visual rerpresentation?3) Dividers between scenes may also help. Again dynamic diagonal lines.4) Even if your cover is black and white, some gray tones to the background could help give the cover some dimension and eat up all of that white space. I think action just kind of bleeds out of these empty spaces.5) The middle character portrait doesn't seem to fit the other two pictures. I would change this to something with more action; like having them firing their sci-fi weapons off panel to an unseen foe; space ships battling in the distance. THAT would be a big change, but hey these are all just suggestions.

I'm old-school graphic design (which really just means that when I was in school, we didn't use computers), and believe in leading the eye intentionally with visual elements. I'm getting that your game is multi-genre and action-packed; so your cover should be too. I have a personal dislike of empty space unless it is intentional (and even then, only if it helps the overall design). You can check out the cover samples at my Ten-Cent Heroes blog to see my work.

I hope that helps. If any of it unclear, let me know. The changes wouldn't take long in InDesign using what you already have here; probably a half hour to make it look sharp.